help pleaseeeeeeeee

# time series
x<-ts(c(-0.2052083,-0.3764986,-0.3762448,0.3740089,0.2737568,2.8235722,-

# ar function
res.ar<-ar(x,aic=TRUE,demean=F)

# call "ar" again and ............
res.ar<-ar(x,aic=TRUE,demean=F)

res.ar<-ar(x,aic=TRUE,demean=F)
res.ar

# time series
x<-ts(c(-0.2052083,-0.3764986,-0.3762448,0.3740089,0.2737568,2.8235722,-

# ar function
res.ar<-ar(x,aic=TRUE,demean=F)

# call "ar" again and ............
res.ar<-ar(x,aic=TRUE,demean=F)

res.ar<-ar(x,aic=TRUE,demean=F)
res.ar

Hi Clara,

Your example works fine on my Apple Mac running
R 2.6.0.

You should include the output of
sessionInfo()
so others will know what platorm you are working on.

# time series
x<-ts(c(-0.2052083,-0.3764986,-0.3762448,0.3740089,0.2737568,2.8235722,-

+ 1.7783313,0.2728676,-0.3273164),start=c(1978,3),frequency=4,end=c(1980,3))

# ar function
res.ar<-ar(x,aic=TRUE,demean=F)

# call "ar" again and ............
res.ar<-ar(x,aic=TRUE,demean=F)

res.ar<-ar(x,aic=TRUE,demean=F)
res.ar

Call:
ar(x = x, aic = TRUE, demean = F)


Order selected 0  sigma^2 estimated as  1.482

res.ar<-ar(x,aic=TRUE,demean=F)
res.ar

Call:
ar(x = x, aic = TRUE, demean = F)


Order selected 0  sigma^2 estimated as  1.482

summary(res.ar)

          Length Class  Mode
order       1     -none- numeric
ar          0     -none- numeric
var.pred    1     -none- numeric
x.mean      1     -none- numeric
aic        10     -none- numeric
n.used      1     -none- numeric
order.max   1     -none- numeric
partialacf  9     -none- numeric
resid       9     ts     numeric
method      1     -none- character
series      1     -none- character
frequency   1     -none- numeric
call        4     -none- call

sessionInfo()

R version 2.6.0 (2007-10-03)
powerpc-apple-darwin8.10.1

locale:
en_CA.UTF-8/en_CA.UTF-8/en_CA.UTF-8/C/en_CA.UTF-8/en_CA.UTF-8

attached base packages:
[1] splines   stats     graphics  grDevices utils     datasets  methods   base

other attached packages:
[1] survival_2.34

loaded via a namespace (and not attached):
[1] tools_2.6.0

Steven McKinney

Statistician
Molecular Oncology and Breast Cancer Program
British Columbia Cancer Research Centre

email: smckinney +at+ bccrc +dot+ ca

tel: 604-675-8000 x7561

BCCRC
Molecular Oncology
675 West 10th Ave, Floor 4
Vancouver B.C.
V5Z 1L3
Canada




-----Original Message-----
From: r-help-bounces at r-project.org on behalf of Clara Cordeiro
Sent: Fri 11/23/2007 7:38 AM
To: r-help at stat.math.ethz.ch
Subject: [R] help pleaseeeeeeeee

Dears Sirs

During my computational work I encountered unexpected behavior when calling
"ar" function, namely
# time series
x<-ts(c(-0.2052083,-0.3764986,-0.3762448,0.3740089,0.2737568,2.8235722,-
1.7783313,0.2728676,-0.3273164),start=c(1978,3),frequency=4,end=c(1980,3))

# ar function
res.ar<-ar(x,aic=TRUE,demean=F)

# call "ar" again and ............
res.ar<-ar(x,aic=TRUE,demean=F)
Error in if (order > 0) coefs[order, 1:order] else numeric(0) :
 missing value where TRUE/FALSE needed
In addition: Warning messages:
1: In log(var.pred) : NaNs produced
2: In if (order > 0) coefs[order, 1:order] else numeric(0) :
 the condition has length > 1 and only the first element will be used

For me it is mysterious why sometimes it works and others it does not,
perhaps I am doing something wrong and stupid :-(

If anyone had already had this problem could you please tell me how you have
solved it?

Thank you for your time.

Best Regards,

Clara Cordeiro

       [[alternative HTML version deleted]]